Device for lifting the uppermost sheet from a pile



4 Dec. 10, 194.0- G, sp gss 1 2,224,802

DEVICE FOR LIFTING THE UPPERIQST SHEET FRO]! A FILE Filed May 23, 1939 4Sheets-Sheet 1 G. SPIESS 2.224,802

DEVICE FOR LIFTING THE UPPERMOST SHEET FROM A FILE Dec. 10, 1940.

Filegi May 23, 1939- 4 Shets-Sheet 2 Dec. 10, 1940. 2,224,802

DEVICE FOR LIF'I'ING THE UPPERMOST SHEET FROM A FILE s. SPIESS 4Sheets-Sheet 3 Filed May 23, 1939 Dec. 10, 1940. e. SPIESS 2,224,802

' DEVICE FOR LIFTING THE UPPERMOST SHEET FROM A FILE Filed May 25, 19394 Sheets-Sheet 4 I Patented Dec. 10, 1940 PATENT OFFICE DEVICE FORIJFTING THE UPPERMOST SHEET FROM A PILE Georg Spiess, Leipzig, GermanyApplication May 23, .1939, Serial No. 275,193

a In Germany May 30, 1938 9 Claims. (01.271-27) This invention relatesto improvements in sheet feeding devices and more particularly to adevice for lifting or raising the uppermost sheet from a flat orfanned-out bank pile for rhythmically or non-rhythmically operatingsheet working machines.

A device for lifting the uppermost sheet from a pile hasalready beenproposed in which a suction nozzle rotatable around a pivot point lies,

in its initial position, above the pile and sucks up the uppermost sheetthereof which is loosened by the blast air of a sheet separating device.Thereupon the suction nozzle describes a circular or rotary movementaround its pivot point for forwarding the sucked-up sheet directly intoa machine operating on it, for example a sizing or printing machine, thedistance of the suction face of the suction nozzle from the pivot pointbein always the same and the sheet being consequently forwarded in acircular path. In another proposed device a plurality of suction nozzlesmovable in a vertical direction lift the uppermost sheet from the pile,which nozzles are moved, for carrying out the sheet forwardingoperation, on a carrier guided in the horizontal forwarding direction ofthe sheet by means of a crank gear.

It has further been proposed to impart to a lifting suction member,besides the lifting or raising movement, also a swinging movementindependent of the former by means of cams. For this purpose, however, acomparatively large number of moving means are necessary and the devicedoes not operate with sumcient certainty orv with suflicient rapidityfor modern machines of high capacity.

In another device as heretofore proposed a gripper suction nozzlereciprocable only vertically is held in its raised position by an aircontrolled locking member with a displaceable air piston. As soon-as thesheet, sucked up by the nozzle, is separated by its forwarding meansfrom the suction opening thereof and thereby communication isestablished with the atmosphere, the pneumatic locking member isreleased and the suction lifting nozzle returns to its position on theuppermost sheet of the pile.

Devices have furthermore been proposed in which a pile feeler isconnected tothe suction nozzles lifting the sheets, in such a mannerthat it takes part in the lifting movement of the nozzle. It has alsobeen proposed to swing the suction nozzle from its otherwise constantlyvertical position positively around a pin, such that the nozzle, drawnby a linkage controlled 'by a cam, strikes against a stationary stop.This swinging movement takes place, however. in a device for lifting theuppermost sheet from a flat or fanned-out bank pile for rhythmically ornon-rhythmically operating sheet working machines of any kind by meansof one or more gripper nozzles. The construction of this novel deviceisvery simple and allows the device to act in the feeding direction of thesheet either at the front or the rear end of the pile, or in anyintermediate position according as to the size of the sheets to be actedupon and other conditions necessitate.

The invention consists in that the gripper nozzle constructed in anysuitable manner carries out from its initial position, in which it lieson or approximately on the particular sheet to be raised at the timefrom the pile, both an automatic movement, effected by the suction airaction of the gripper nozzle, for lifting the sheet and also a swingingmovement around a pivot point which is effected in the sheet forwardingdirection by other suitable means.

The movement of the gripper nozzle in the for warding direction of thesheet can be either a positive movement controlled, for example, by acam and carried out rhythmically or a nonrhythmic movement in which thegripper nozzle swingable around a pivot point is taken or carried alongin the forwarding direction of the sheet by the forward pull thereof.

In accordance with the invention the suction action of the grippernozzle is adjustable as regards time by a controllable stop, such as anadjusting screw influencing the device for providing a flow ofatmospheric air into the suction conduit.

A further feature of the invention consists in that, in complete orapproximate agreement with the duration of movement of the grippernozzle or the action of the suction air in the latter,

blast air is forced from a known pneumatic sheet' separating deviceunderneath the raised sheet. Both kinds of air are made dependent on oneanother so that the best possible saving of suction and blast air isobtained.

In, accordance with the invention, the gripper nozzle, which may be ofany suitable kind and swingable around a pivot point, is held, duringits outward swinging movement in the direction of the sheet feeding, inits raised sucking position by a suitable locking means, which isreleased automatically, for example by contact against a stop, onlytowards the end, or on, or after, the

return swinging movement of the gripper nozzle into its initialposition, whereupon the gripper nozzle can again take up its position onor approximately on the particular sheet to be raised from the pile.

Moreover, in accordance with the invention, a mutual displacement of thesheets is entirely avoided even if they are strongly adhering to oneanother owing to electric or other influences, because the air pocketunder the sheet, produced in known manner by the blast air of the sheetseparating device acting on the under side of the sheet, is maintainedin its intensity in a manner not hitherto attained.

The gripper nozzle is, according to the invention, arranged on aswinging frame with a feeler constantly resting upon the sheet pile,which feeler in the known manner automatically regulates the suctionposition of the gripper nozzle corresponding to the height of the pile.n the swinging frame, moreover, is arranged the blast nozzle for thesheet separation, the position of which, relatively to the pile height,is likewise automatically regulated so that its blast action for thepurpose of loosening and separating the uppermost sheet from the pilealways commences at the correct position. The swinging frame, moreover,consists of two or more. relatively displaceable individual parts, whichcan be formed as a telescopic-like suction conduit for the grippernozzle. According to the relative displacement of the individual partsof the swinging frame, the parts arranged on it, such as the grippernozzle, the pile feeler and, if necessary, the blast nozzle can be madeto conform to any particular size of sheet. The swinging frame is,moreover, in accordance with the invention swingable out of its workingposition for the purpose of rendering the whole device inoperative.

In order that the invention may be fully understood I shall now describesome embodiments thereof by way of example by reference to theaccompanying diagrammatic drawings, in which:

Figs. 1 and 2 are a side view, and a front view of the main portion, ofone form of device for the rhythmic feeding of sheets from a flat pile.

Fig. 3 is an elevation of a modified arrangement for the non-rhythmicfeeding of sheets from a fanned-out bank pile.

' Figs. 4-7 are part sectional side elevations of a further modifieddevice and showing the gripper nozzle in various diflerent workingportions,

and

Figs. 8 and 9 areside views of the swinging frame showing the grippernozzle, pile feeler and blast nozzle in different working positions.

Referring first to the embodiment shown in. Figs. 1-. and 2, a rod 3issecured in bearings 2 on a side frame wall I, and beneath the rod I iscarried a constantly rotating shaft 4 having abevel wheel gearing 5arranged at one end thereof. On the rod 3 and the shaft 4 is arranged acarrier member 8 which is displaceable and fixable in the forwardingdirection, indicated by the arrow in Fig. 1, of the uppermost sheet Iraised from the pile I. The adjustment is effected according torequirements and corresponding to the size of the sheets. On the carriermember I is swingably carried at 9 a hollow member 8, which a spring I.constantly tends to bring into the position shown. In the lower part ofthe hollow member I is displaceably carried, after the manner of apiston, a gripper nozzle II, which is supplied with suction air by meansof air channels 12 and a pipe l3.

for connection to a suction pump, arranged in the carrier member 8. Aspring-loaded valve l4 opening towards the outer air is arranged in theair channel in the carrier member 6, which valve is controlled by a camI5 arranged on the shaft 4, and in the hollow member 8 is arranged asimilar valve l1 controlled by an adjusting screw IS on the carriermember 6. A cam disc l8, against which is pressed a roller IS on thehollow member 8 under the action of the spring I0, is secured on theshaft 4 for the purpose of effecting the swinging movement of thegripper nozzle H. The conduit 20 serves for efiecting in the knownmanner the sheet separation by means of blast air. In the two framewalls I is, moreover, arranged adjacent the feed table 23 a forwardingroller 2| with a rhythmic roller 22 co-operatihg with it. The sheets canbe withdrawn and forwarded from the pile I eithe individually oroverlapped.

The above described device operates in the following manner:

In the position of the individual parts indicated in the drawings, onthe further rotation of the shaft 4, the blast air in the conduit 20 forseparating the sheet from the pile I and the suction air in the hollowmember 8 and the gripper nozzle II is simultaneously positively started.The uppermost sheet of the pile is sucked on to the nozzle il, wherebythe latter,

owing to the fact that its suction opening is closed by the sucked upsheet, is drawn, after the manner of a piston, into the hollow member 8to an advantageously adjustable height and the uppermost sheet I israised from the pile. Then or directly thereon the gripper nozzle llswings, owing to the rotation of the cam [8, in a clockwise direction.In order to prevent the sheet from being released from the suctionnozzle ll only in a rest position thereof, the adjusting screw [6 is soadjusted that by the striking of the valve II on the adjusting screw,air is introduced into the gripper nozzle il shortly before the end ofthe complete swinging-out movement thereof, and in this way the relievedsuction nozzle ii in the position ll frees the sheet 1', which, in themeantime or now, is seized at the other end by the suction roller 2| orthe forwarding rollers 2|, 22 and brought to the feed table 23. Thegripper nozzle ll arrives in the position II in that it is drawn, afterthe manner of a piston, into the hollow member 8 and swung around thepivot point 9. As the sheet I is released during the swinging movementof the gripper nozzle H and is not withdrawn from a stationary suctionnozzle, the sheet is very favourably treated and, in the case of aprinted sheet, itsrprinting is not smeared. Simultaneously with theentrance of air into the gripper nozzle ll,which takes place through thevalve l4 opened by the cam IS, theblast air in the conduit 20 ispositively stopped, The roller" l9, then runs during the continuedrotation of the shaft 4, on to the lowest part of the cam l8 and thegripper nozzle II is returned by the spring [0 into its initial positionshown in the drawings, in which it again lies on the next' uppermostsheet of the pile I or approximately on it, whereupon the cycle isrepeated.

The gripper nozzle ll, secured against falling out of the hollow-memberI, can, by suitable displacement of the carrier member 8 on the rod 3and the shaft 4, contrary to the arrangement shown in Fig. 1, be causedto act at the other forward end of the sheet pile directly in front 76of the forwarding rollers 2|, 22 or the suction roller 2|, or manyintermediate position.

blast air in the sheet separating conduit and tial position.

simultaneously the suction air for the gripper nozzle II, the latter isdrawn by the suction air after the manner of a piston into the hollowmember 8 and the rear part of the uppermost sheet I is drawn up with it,whereupon the gripper nozzle ll, without the use of any other mechanicalmoving means, swings solely under the action of the pull of the suctionroller 2| on the sheet seized by it, or, by the pull of the sheet, intothe position II. If, by the striking of the valve II on the adjustingscrew ii, the suction air conduit of the gripper nozzle Ii is thenconnected with the atmosphere, the nozzle Ii frees the sheet adhering toit. The gripper nozzle N then swings back, under the action-of thespring It), automatically into the initial position indicated in thedrawings and lies automatically on the next uppermost of the scale-likearranged sheets of the fanned-out bank pile I or approximately thereon,whereupon the whole operation is repeated.

'In the embodiment shown in Figs. 4-9 the valve I] and the adjustingscrew ii are replaced by air channels l8 and i1. Moreover, a roller 24serving as a pile feeler is carried in the carrier member 6 by means ofa forked rod displaceable therein and fixable by means of two nuts 25.

In the embodiment according to Figs. 4-7, the gripper nozzle l i isshown in Fig. 4 in its ini- It sucks the uppermost sheet I of thefanned-out bank pile I under the influence of the blast air coming fromthe separating nozzle 20. When this has taken place, see Fig. 5, thegripper nozzle H is drawn up into the hollow member 8 and then swings inthe abovedescribed manner around the hollow axis 9, Fig. 6. A lockingpawl 29 arranged on the hollow member 8, moreover, is released from thestop 28 on the hollow member 8 and is displaced under the action ofa-spring automatically beneath a projection 30 on the gripper nozzle II.The latter is thus now locked in its raised position within the hollowmember 8. If now, according to Fig. '7, the two air channels I6, l'lcome into register with one another for the purpose of allowing theinflow of air into the hollow member 8 and the gripper nozzle II, thegripper nozzle ll releases the sheet I and returns automatically underthe action of the spring l0 into its initial position shown in Fig. 4.Shortly before, or on, or

after the finish of this return swinging movement the locking pawl 29engages the preferably adjustable stop 28 and thus unlocks theprojection 30 of the gripper nozzle II, which can then return to itsposition on or approximately on the now uppermost sheet of thefanned-out bank pile 1.

In the embodiment according to Figs. 8 and 9, on the supporting table 3|for the fanned-out bank pile I is arranged a-lever 32 and, moreover, abell .crank lever 28 carried in a frame and provided with a hand lever21. To these two levers 26 and 32 is pivoted a swinging frame 3'consisting of two telescope-like displaceable tubes, which frame carriesat its other end the carrier member 6 with the hollow member 8 andgripper nozzle I I, the pile feeler 24 and the sheet separating nozzle20. Owing to the suspension of the swinging frame 3' on the levers 26and 32 the whole device can, by means of the hand lever 21, be swungupwardly out of its operative position according to Figs. 8 and 9 intoan inoperative position. v

The pile feeler 24 is so adjusted that the gripper nozzle l I is alwaysarranged at a suitable distance from the pile I or the uppermost sheet Ithereof. From its initial position, Fig. 8, the gripper nozzle ll swingsout with the sucked-up sheet 1' as shown in Fig. 9, releases the sheetin the registering position of the air channels it and i1 and returns,under the action of the spring to, into its initial position shown inFig. 8 and again comes to rest automatically on or approximately on thenext uppermost sheet. If a thinner or more yielding part of the sheetpile comes under the feeler 24, then the position of the gripper nozzleII and the sheet separating nozzle 20 is automatically correspondinglyvaried. In Fig. 9 the individual parts of the swinging frame 3' aremachine, comprising the sub-combination of: a

support; a suction gripper pivotally mounted on said support; pneumaticmeans associated with said gripper for moving the topmost sheet of thepile into engagement with said suction gripper; suction producing meansfor causing the sheet to adhere to said gripper and for causing thelatter to be raised vertically upwardly away from the pile; means,independent of said suction means, for swinging said gripper and thesheet adhering thereto, around its pivot point in the direction of feedof the sheets so as to advance the raised sheet towards the sheetworking machine; and adjustable means for putting said suction producingmeans out of operation for the purpose of releasing the sheet from saidsuction gripper as required.

'gripper, said means also causing said gripper to be raised verticallyupwardly to raise said sheet from the pile; means, independent of saidsuction producing means, for swinging said gripper and the sheetadhering thereto, around its pivot point in the direction of feed of thesheets so as to advance the raised sheet towards thesheet workingmachine; and adjustable means for putting saidsuction producing meansout of operation for the purpose of releasing the sheet from saidsuction gripper as required, said means comprising a stop on saidsupport and a valve on said suction gripper, said valve being adapted,on coming into contact with said stop, to open said gripper to theatmosphere.

3. A device of the kind specified for use in the feeding of sheets froma pile to a sheet working machine, comprising the sub-combination of: asupport; a hollow tube, having an air outlet channel therein, carried bysaid support; said tube having a depending sleeve; a hollow tubeslidably mounted in said depending sleeve; a suction gripper carried atthe lower end of said tube; a sleeve mounted in said first-mentionedhollow tube, said sleeve having a peripheral opening therein adapted toregister with the air outlet channel in said first hollow tube onrotation of said sleeve; and a second peripheral opening adjacent saiddepending tube; means connected to said rotatable sleeve for producingsuction in said suction gripper, for drawing the topmost sheet of thepile into engagement with said gripper, and for causing saidgripper-carrying-tube to move upwardly after the manner of a piston, insaid depending sleeve thereby raising said gripper and the sheetadhering thereto, vertically; and a sheet forwarding device associatedwith said sheet raising device, the arrangement being such that on theraising of the sheet by said gripper, said sheet is seized by saidforwarding device and fed towards the sheet working machine, saidsuction gripper being taken along by said sheet with simultaneousswinging of said first-mentioned hollow tube around said inner sleeveuntil said outlet channel and peripheral .opening register with oneanother, whereupon said suction gripper is opened to the air and thesuction action thereof is cut off and said sheet is released; and meansfor returning said suction gripper to its initial vertical position.

4. A device of the kind specified for use in the feeding of sheets froma pile to a sheet working machine, comprising the sub-combination of: asupport; a movable suction gripper for raising the topmost sheet fromthe pile carried by said support; means associated with said gripper forapplying suction to said suction gripper to cause the topmost sheet ofthe pile to adhere thereto and for moving said gripper together with thesheet adhering thereto, vertically upwardly away from the pile; means,independent of said suction producing means, for moving said gripper, inthe raised position thereof, in the direction of feed of the sheets; andreleasable means for retaining said suction gripper in the verticallyraised position.

5. A device of the kind specified for use in the feeding of sheets froma pile to a sheet working machine, comprising the sub-combination of: asupport; a suction gripper pivotally mounted on said support; suctionproducing means associated with said gripper for causing the topmostsheet of the pile to be drawn into engagement with and to adhere to saidsuction gripper, said means also causing said gripper to be raisedvertically upwardly to raise said sheet from the pile; means,independent of said suction producing means, for swinging said gripperand the sheet adhering thereto, around its pivot point in the directionof feed of the sheets so as to advance the raised sheet towards thesheet working machine; and a releasable locking pawl pivoted to saidsupport operable to engage said suction gripper in the raised positionof the latter for the purpose of retaining said gripper in the raisedposition during the swinging thereof in the sheet forwarding direction.

6. A device of the kind specified for use in the feeding of' sheets froma pile to a sheet working machine, comprising the sub-combination of: asupport; a suction gripper pivotally mounted on said support; suctionproducing means associated with said gripper for causing the topmostsheet of the pile to be drawn into engagement with, and to adhere tosaid suction gripper, said means also causing said gripper to be raisedvertically upwardly to raise said sheet from the pile; means,independent of said suction producing means, for swinging said gripper,and the sheet adhering thereto, around its pivot point in the directionof feed of the sheets so as to advance the raised sheet towards thesheet working machine; a releasable locking pawl pivoted to said supportoperable to engage said suction gripper in the raised position of thelatter for the purpose of retaining said gripper in the raised positionduring the swinging thereof in the sheet forwarding direction; means forreleasing the sheet from the said gripper; means for returning saidgripper to its initial vertical position; and a stop carried by saidsupport adapted, on return movement of said gripper, to release saidlocking pawl and allow said gripper to move downwardly substantially asdescribed.

7. A device of the kind specified for use in the feeding of sheets froma pile to a working machine, comprising the sub-combination of: asupport; a swinging frame pivotally suspended from said support; ahorizontally movable carrier member mounted on said swinging frame; apivoted suction gripper mounted on said carrier; means for moving saidcarrier horizontally on said frame to adjust the initial position ofsaid gripper with respect to the pile; means, associated with saidcarrier member, for applying sucion to said gripper to cause the topmostsheet of the pile to adhere thereto and for moving said gripper,together with said sheet, vertically upwardly away from the pile; andmeans, independent of said suction producing means, for swinging saidgripper, in the raised position thereof, in the direction of feed of thesheets.

8. A device of the kind specified for use in the feeding of sheets froma pile to a working machine comprising the sub-combination of: asupport; a swinging frame pivotally suspended from said support; ahorizontally movable carrier member mounted on said swinging frame; apivoted suction gripper; a pile feeler and a sheet loosening andseparating device mounted on said carrier; means for moving said carrierhorizontally on said frame to adjust the initial position of saidgripper with respect to the pile; means, associated with said carriermember, for applying suction to said gripper to cause the topmost sheetof the pile to adhere thereto and for moving said gripper, together withsaid sheet, vertically upwardly away from the pile; and means,independent of said suction producing means, for swinging said gripperin the raised position thereof, in the direction of feed of the sheets.

9. A device of the kind specified for use in the feeding of sheets froma pile to a working machine, comprising the sub-combination of: asupport; a swinging frame pivotally suspended from said support, saidframe comprising at least two mutually displaceable parts, whereby thesize of said frame may be adjusted in conformity with the size of sheet;a movable suction gripper pivoted to said swinging frame; means forapplying suction to said gripper to cause the topmost sheet of the pileto adhere thereto and for moving said gripper, together with said sheet,vertically upwardly away from the pile; means, independent of saidsuction producing means for swinging said gripper in the direction offeed of the sheets; and means for moving said swinging frame into andout of operative position substantially as described.

GEORG SPIESS.

